The US House of Representatives will vote next month on legislation authorising a lawsuit against President Barack Obama, the speaker has said.

Republican House Speaker John Boehner accused Mr Obama of illegally failing to carry out laws passed by Congress.

He said Mr Obama, a Democrat, was guilty of "aggressive unilateralism" in his use of executive authority.

The White House argues Mr Obama acts within his Constitutional authority and on behalf of the American people.

"On matters ranging from healthcare and energy to foreign policy and education, President Obama has repeatedly run an end-around on the public and Congress," Mr Boehner wrote in a letter to the Republican House caucus.

He also accused Mr Obama of "ignoring some statutes completely, selectively enforcing others and at times, creating laws of his own".

White House press secretary Josh Earnest dismissed the allegations.

"We feel completely confident that the president was operating within his authority as the president of the United States to take these steps on behalf of the American people," he said.

'Desperate political stunt'

The Republican Party controls the House of Representatives and enough votes in the Senate to block legislation in that chamber, effectively halting Mr Obama's legislative agenda since the beginning of 2011.

In his state of the union speech in January, Mr Obama vowed to use his "pen and phone" to circumvent Congress through executive action, provoking Republican denunciations of an "imperial presidency".

Mr Obama in recent months has issued two executive orders aimed at erasing gender disparities in pay among the government workforce, and announced plans to sign an order banning federal government contractors from discriminating against gay and transgender workers.

In June 2012, Mr Obama sidestepped Congress on immigration reform, issuing an executive order halting deportation of some illegal immigrants brought to the US as children. Another executive order allowed some illegal-immigrant relatives of US military members to remain in the country.

Republicans were also quick to challenge Mr Obama's decision to postpone legal requirements under his signature healthcare law.

Conservatives denounced the move as unilateral and a violation of the law, calling on the White House to throw out all the Affordable Care Act's coverage mandates.

The announcement on Wednesday of the planned lawsuit escalates the bitter political battle between Republicans and Democrats ahead of mid-term elections in November.

At stake are control of the House and the Senate.

Congressman Steve Israel, chair of the Democratic Congressional Campaign Committee, criticised House Republicans for the manoeuvre.

"[It's a] reprehensible waste of taxpayers' money and a desperate political stunt meant to gin up the Republican base at a time when House Republicans are historically unpopular," he said.